The advent of digital image capture technologies has revolutionized the photography industry. Digital cameras can now take pictures in high-resolution formats in which each image has several million pixels. The size of such images, along with the limited storage capacity typically available, has prompted the development of many different image compression algorithms. Many of these algorithms function based on grouping pixels of similar colors together and removing variations that are not generally perceptible to the human eye.
Light field cameras capture not just a two-dimensional image, but also light field data related to the angle of incidence of light received at various locations within the image. Such data is captured by causing the light to pass through a microlens array (MLA) positioned between the main lens and the image capture sensor. The resulting image may have a plurality of pixel clusters, each of which represents light that passed through a single microlens of the microlens array. Capture of directional information in this manner facilitates various operations, such as refocusing and other forms of image manipulation that are not possible with conventional images.
Because they include significant amounts of information not present in conventional images, light field image files may be very large. Unfortunately, the presence of a microlens pattern superimposed on the representation of the scene can result in rapidly varying content within the light field image file; this high-frequency spatial variation in pixel intensity can result in poor performance when applying conventional image compression techniques.